Automatic alternating-current contact apparatus.



No. 884,066. V A PATENTED APR. 7, 1908.

I o. B. L. BROWN. AUTOMATIC ALTBRNATING CURRENT CONTACT APPARATUS.

APPLICATION FILED NOV. 7, 1903,

2 SHEBTSSHEBT 1.

- llilzwslsex fihzfl No. 884,066. PATBNTED APR. 7, 1908.

c. E. LI BROWN.

AUTOMATIC ALTBRNATING CURRENT CONTACT APPARATUS.

APPLICATION FILED NOV. 1, 1903.

2 SHEETS-SHEET 2.

a a in y iii mega" A A fizz 67250 rents.

UNITED STATES PATENT OFFICE.

CHARLES EUGEN LANGELOT BROWN,

GESELLSCHAFT BROWN, BOVERI &

OF BADEN, SWITZERLAND, ASSIGNOR TO AGTIEN- 00., OF BADEN, SWITZERLAND, A FIRM.

/ AUTOMATIC ALTEBNATING-C'U'RRENT CONTACT APPARATUS.

Specification of Letters Patent.

' Patented April 7,1908.

Application filed November 7, 1903. Serial No. 180,201.

'in Automatic Alternating-Current Contact Apparatus, of which the following is a specific-ation.

In many cases it-is advisable, in' electric circuits, especially in high-tension circuits, to use s ecial automatic cut-outs instead of the wel known fuses. It is necessary, of course, that such cut-outs are so made that the cutting of the current is done in the same way as by fuses, i. (5., it is necessary to arrange them in such a way that they are automatically disconnected as soon as the current attains a predetermined intensity at or within a predetermined time.

Such a disconnecting device forms the ob- -ject of the present invention. It permits of predetermining at will both the intensity at which contact shall be made, and the time (reckoned from the moment when this intensity is reached) at or within which this takes place. 1

Referring to the drawings in which like parts are similarly 'designatedFigure 1 is a ont view, and Fig. 2 a side view (taken at right angles) of the device for ordinary cur ig. 3 is a plan of a three-phase circuit containing each phase) and showing the way in which they operate in connection with cut-outs. Figs. 4 and 5 are side and front views (taken at right angles to each other) of a device shown'in Figs. 1 and 2, but arranged for reverse currents. Fig. 6 is a corresponding plan of connections showin one of the devices placed in one of the p ases of a threephase circuit.

Referring to Figs. 1 and 2 of the accompanying drawings, the following is a description 0 one of the ways of carrying the invention into effect: A disk 10f conducting but nonmagnetic material is so placed between the poles of a laminated horse-shoe iron-core-3,;

that it is capable of rotating'between these soles, between which and the sides of the isk but a small space is left. The ends of the oles are partly provided with a copper win ing 4 of very small resistance which is short circuited on itself. The laminated iron core carries a coil 2 which is connected, either directly or indirectly, by means of a weight three such devices (one indisconnecting current transformer, with the circuit intended to be broken. The poles of a permanent magnet 9 are placed on each side of the disk, in a similar manner to those of the beforementioned iron core. Such a structure may be termed 'an induction motor. On the axis of the disk a small drum 5 is mounted, on

which, when it turns, a cord 6 carrying a 7 is wound. Near the axis, next to the cord, there is a contact sprin 8 laced in a separate circuit, which latter 1S\ 0 osed by the weight 7 touching the spring 8.

The manner inwhich the device operates is as follows: The alternatin current electro-magnet composed of the aminated iron core with short circuited copper winding before described produces a turning moment on the axis of the disk, the strength of which depends on the intensity of the current in 'the main circuit. This turning moment is counteracted by the weight suspended by the cord on the drum mounted on the axis of the disk. The disk will therefore be made to rotate as soon as the turning moment produced by the main circuit become stronger than the weight. In revolving, the disk winds up the cord carrying the weight and the latter, as soon as it touches the contact spring, closes the separate circuit in which t e latter is placed and by means of which a cut-out is dlsconnected. According to the size of the Wei ht, the intensity required to produce a su cient turning .moment for raising it varies, and moreover, the time from the moment when the intensity becomes strong enough to raise the weightuntil the weight reaches the contact s ring also varies according to the length 0 the cord. By regulating the length of the cord and the size of the weight, it is therefore possible to predetermine at will both the intensity at which contact shall be made, and the time at or within which this result is roduced. The permanent magnetis rovi ed for damping the rotation of the isk and to prevent the same from. oscillating.

In Fig. 3 the device is shown applied to a three-phase circuit, a se arate disconnecting device being provided or each phase. In this figure 15 1 stands for the current transformers, 16 for the ammeters A, M for the devices, 17 for .the contacts placed in a separate circuit, 13 for the apparatus providing this latter circuit with current, 12 for the magnet coil acting on the cut-out 11 when the contacts 17 are closed. The conductors for the contacts are connected in parallel, so that the closing of one of the contacts sufilces for operatmg the cut-out.

If the device above described. is intended to be used for reverse current, two electromagnets are placed so as to act on the disk; these electro -magnets have cores of laminated iron, but their oles are not, as in the previous case, provi ed with a short-circuited copper Windin The coil of one of them is connected witi the main circuit, or, by means of a current transformer, with a clrcuit de ending on the main circuit, whereas the other coil is placed in a shunt for voltage across the other two phase leads.

arrangement of this kind is illustrated by Figs. 4 and 5, in which 1 stands for the dlsk capable of revolving, 2 for one of the coils, 3 for the corresponding iron core, 4 for the other coil, 5 for the drum, 6 for the cord and 7 for the weight. Fig. 6 shows the connections of such a device as placed in a three-phase circuit, the connections being shown but for one phase, 15 stands here for a current transformer, 15 for a transformer, 16 for an ammeter A, V for a voltmeter, M' for a disconnecting device for reverse current, 17 one .of the contacts intended to be closed by the latter, 13 for the apparatus roducing current for the separate circuit, 12

or a magnet coil acting on the cut-out 11.

The device for reverse current 0 crates as follows: The two electro-magnets 0th roduce a turning moment on the disk, w ich tends in a certain direction when the current flows in the ordinary direction; as soon as reverse current appears in the circuit, the turning moment changes, and the disk becomes free to rotate in the direction in which it is impelled b the reverse current, whereas it is prevente from rotating in the other directlon by a suitable arran ement such as a stop or pin on the disk. hen reverse current is produced in the main circuit, the latter is therefore cut in the manner above described.

Having thus described in invention, what I claim as new therein and esire to secure by Letters Patent, is:

1. In a circuit closer means to produce an alternating current field, an induction device movable in the field a weight lifted by a plurality of revolutions of said device and circuit terminals closed when the weight has reached its upper limit of movement.

2. In a circuit closer means to produce an alternati current field, an induction disk in said fie d, an ad'ustable weight lifted by a plurality of revolutions of said disk and circuit terminals closed by said weight when it has reached its limit of movement.

3. In a circuit closer means to produce an alternating current field, a disk rotatable in the field, an adjustable wei ht, a sus ension therefor connected to said fevice an circuit closing terminals closed by the weight when lifted, the time of closure being controlled by the length of said suspension.

4. The combination with a main circuit; of a cut-out, a rotatable induction device responsive to variations of current in the main circuit and capable of making a number of revolutions to operate said cut-out, weights suspended from the induction device to adjust the operation of the induction device to currents of different intensity in the main circuit, and an adjustable sus ension for the weights to vary the number 0 revolutions of the device and thereby the time of operating the cut-out after the current has reached the selected intensity, substantially as described. 5. The combination with a main circuit; of a cut-out, an induction device rotatable in a vertical plane and indirectly included in said circuit to operate the cut-out, an adjustable suspended weight to adjust the operation of the induction device to currents of different intensity and means tovary the distance traveled by said weight to vary the number of revolutions of the induction device and thereby the time of operating the switch after the current has reached the selected intensity, substantially as described.

6. The combination with a main circuit; of a circuit closer comprising a field inducing device, a rotating element inductively operated by the field inducing device, electric terminals, a flexible suspension and a weight on said suspension lifted by the rotating element to close circuit between the termlnals, substantially as described.

7. The combination with a main circuit; of a circuit closer comprising an electromagnet, a non magnetic disk, a spindle therefor, a drum on the spindle, a weight suspended from and adapted to be wound upon the drum, and electric terminals closed by said weight, substantially as described. I

8. The combination with a main circuit; of a circuit closer comprising an electro-magnet, a disk, a spindle therefor, a second magnet, said disk operating within the fields of both magnets, a drum on the spindle, a weight suspended from and adapted to be wound upon the drum and terminal contacts closed by said weight, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

' CHARLES EUGEN LANCELOT BROWN.

. Witnesses:

Monrrz Vnrrrr, A. LIEBERKNECHT. 

